A male octopus has escaped from the National Aquarium of New Zealand in Napier through a narrow pipe and has returned to the ocean.The octopus slipped through a small gap in his enclosure, slid across a wet floor, then squeezed through a 150-millimetre-diameter (5.9 inches) pipe. The octopus was given to the aquarium two years ago after being rescued from a crayfish pot.